Medical probe with electrode guide for transurethral ablation

Abstract

A medical probe for the treatment by radio frequency ablation of a target volume in tissue of a human having a urethral channel extending into a base of a bladder along a longitudinal axis. The probe comprises an elongate probe member having proximal and distal extremities and sized so that it can be introduced into the urethra. The elongate probe member has a passage extending from the proximal extremity to the distal extremity. Guide cannulae are mounted in the passage of the elongate probe member and have proximal and distal extremities with the distal extremities of the guide cannulae being in the vicinity of the distal extremity of the elongate probe member. Each of the guide cannulae has a lumen extending therethrough from the proximal extremity to the distal extremity. A radio frequency conductive electrode is disposed in each lumen. A control handle is secured to the proximal extremity of the elongate probe member. The control handle is connected to each radio frequency electrode whereby each radio frequency electrode can be advanced and retracted.

We claim: 
     
       1. A medical probe for the treatment by radio frequency ablation of target volumes in tissue of a human having a urethral channel extending into a base of a bladder along a longitudinal axis comprising an elongate probe member having proximal and distal extremities and being sized so that it can be introduced into the urethra, the elongate probe member having at least one passage extending from the proximal extremity to the distal extremity, guide cannulae mounted in the at least one passage of the elongate probe member and having proximal and distal extremities with the distal extremities, of the guide cannulae being in the vicinity of the distal extremity of the elongate probe member, each of the guide cannulae having a lumen extending therethrough from the proximal extremity to the distal extremity, a radio frequency conductive electrode disposed in each lumen, a layer of insulating material coaxially disposed about each of the radio frequency electrodes, handle means coupled to the proximal extremity of the elongate probe member and including hand operable means secured to the radio frequency electrodes for advancing the radio frequency electrodes from the guide cannulae into the target volumes. 
     
     
       2. A probe as in claim 1 wherein the handle means includes means for causing bending of the distal extremities of the guide cannulae to thereby control the direction of penetration of the radio frequency electrodes. 
     
     
       3. A probe as in claim 2 wherein the distal extremity of each of the guide cannulae is provided with a cylindrical wall, the cylindrical wall having at least a portion thereof containing a plurality of longitudinally spaced apart circumferentially extending slots subtending less than 360 degrees formed therein, the slots facilitating bending of the guide cannulae in said flexible portions of the distal extremities of the guide cannulae. 
     
     
       4. A probe as in claim 3 wherein the slots are circumferentially aligned to provide a backbone extending longitudinally of each said flexible portion so as to permit bending in only a single direction. 
     
     
       5. A probe as in claim 3 wherein said flexible portions can be bent through an angle approximating 90 degrees. 
     
     
       6. A probe as in claim 1 wherein the handle means includes means for presetting the maximum distance the radio frequency electrode in each of the lumens can be extended distally. 
     
     
       7. A probe as in claim 1 wherein the distal extremity of each of the guide cannulae extends through a curved path for directing the radio frequency electrodes sidewise of the longitudinal axis. 
     
     
       8. A probe as in claim 1 together with a scope carried by the control handle and having a distal extremity in the vicinity of the distal extremity of the elongate probe member. 
     
     
       9. A probe as in claim 1 wherein the distal extremity of each of the guide cannulae is bendable. 
     
     
       10. A medical device for use with an elongate probe member to treat by radio frequency ablation a target volume in tissue of a human having a urethral channel extending into the base of a bladder along a longitudinal axis, the elongate probe member having proximal and distal extremities and being sized so that it can be introduced into the urethra and having a passage extending from the proximal extremity to the distal extremity, comprising a guide cannula adapted to mount in the passage of the elongate probe member and having proximal and distal extremities, the distal extremity of the guide cannula being in the vicinity of the distal extremity of the elongate probe member when the guide cannula is mounted in the passage of the elongate probe member, the guide cannula having a lumen extending therethrough from the proximal extremity to the distal extremity, a radio frequency conductive electrode disposed in the lumen of the guide cannula, a layer of insulating material coaxially disposed about at least a portion of the radio frequency electrode, handle means coupled to the proximal extremity of the guide cannula and including hand operable means secured to at least the radio frequency electrode for advancing and retracting the radio frequency electrode and the layer of insulating material with respect to the guide cannula and hand operable means for causing bending of the distal extremity of the guide cannula to thereby control the direction of penetration of the radio frequency electrode into the tissue. 
     
     
       11. A medical device as in claim 10 wherein the distal extremity of the guide cannula is provided with a cylindrical wall having at least a portion thereof containing a plurality of longitudinally spaced apart circumferentially extending slots subtending less than 360 degrees formed therein, the slots facilitating bending of the guide cannula in said portion of the distal extremity of the guide cannula. 
     
     
       12. A medical device as in claim 11 wherein said slots are circumferentially aligned to provide a backbone extending longitudinally of the flexible portion so as to permit bending in only a single direction. 
     
     
       13. A medical device as in claim 10 wherein the layer of insulating material is in the form of an insulating sleeve movable longitudinally relative to the radio frequency electrode. 
     
     
       14. A medical device as in claim 10 together with an additional guide cannula adapted to mount in the elongate probe member and similar to the first named guide cannula, an additional radio frequency conductive electrode disposed in the lumen of the additional guide cannula and a layer of insulating material coaxially disposed about the additional radio frequency electrode, means secured to at least the additional radio frequency electrode for advancing and retracting the additional radio frequency electrode and said layer of insulating material with respect to the additional guide cannula. 
     
     
       15. A medical device as in claim 14 wherein the additional guide cannula extends alongside the first named guide cannula, the guide cannulae having portions between their proximal and distal extremities, means for fastening together the portions of the guide cannulae. 
     
     
       16. A medical device for the treatment by radio frequency ablation of a target volume in tissue of a prostate of a human having a urethral channel extending into a base of a bladder along a longitudinal axis comprising an elongate probe member having proximal and distal extremities and having a passage therein extending from the proximal extremity to the distal extremity, the elongate probe member being sized so that it can be introduced into the urethra, a guide cannula mounted in the passage of the elongate probe member and having proximal and distal extremities, the guide cannula having a lumen extending therethrough from the proximal extremity to the distal extremity, a radio frequency conductive electrode disposed in the lumen, a layer of insulating material coaxially disposed about the radio frequency electrode, handle means coupled to the proximal extremity of the elongate probe member, the handle means including finger actuatable means secured to the radio frequency electrode for advancing the radio frequency electrode from the guide cannula into the target volume, the distal extremity of the guide cannula having a curvature for directing the radio frequency electrode sidewise of the longitudinal axis into the tissue of the prostate. 
     
     
       17. A device as in claim 16 wherein the handle means includes means for adjusting the curvature of the distal extremity of the guide cannula. 
     
     
       18. A medical probe for the treatment by radio frequency ablation of a target volume in tissue of a human having a urethral channel extending into a base of a bladder along a longitudinal axis comprising an elongate probe member having proximal and distal extremities and being sized so that it can be introduced into the urethra, the elongate probe member having a passage extending from the proximal extremity to the distal extremity, a guide cannula mounted in the passage of the elongate probe member and having proximal and distal extremities with the distal extremity of the guide cannula being in the vicinity of the distal extremity of the elongate probe member, the guide cannula having a lumen extending therethrough from the proximal extremity to the distal extremity, a radio frequency conductive electrode disposed in the lumen, handle means coupled to the proximal extremity of the elongate probe member, the handle means including means secured to the radio frequency electrode for advancing and retracting the radio frequency electrode relative to the guide cannula and hand operable means accessible from the proximal extremity of the elongate probe member for selectively bending the distal extremity of the guide cannula to thereby control the direction of penetration of the radio frequency electrode into the tissue. 
     
     
       19. A probe as in claim 18 wherein the distal extremity of the guide cannula is provided with a cylindrical wall, the cylindrical wall having at least a portion thereof containing a plurality of longitudinally spaced apart circumferentially extending slots subtending less than 360 degrees formed therein, the slots facilitating bending of the guide cannula in said portion of the distal extremity of the guide cannula. 
     
     
       20. A probe as in claim 19 wherein the slots are circumferentially aligned to provide a backbone extending longitudinally of the flexible portion so as to permit bending in only a single direction. 
     
     
       21. A device as in claim 18 together with a layer of insulating material coaxially disposed about the radio frequency conductive electrode. 
     
     
       22. A medical device for treatment by radio frequency ablation of a target volume in tissue of a human having a urethral channel extending into the base of a bladder along a longitudinal axis comprising an elongate probe member having proximal and distal extremities and having a passage extending from the proximal extremity to the distal extremity, the elongate probe member being sized so that it can be introduced into the urethra, elongate guide means mounted in the passage of the elongate probe member and having proximal and distal extremities with the distal extremity of the elongate guide means being in the vicinity of the distal extremity of the elongate probe member, the elongate guide means having at least first and second lumens extending therethrough from the proximal extremity to the distal extremity, a radio frequency conductive electrode disposed in each lumen and having a distal portion, a layer of insulating material disposed on each said radio frequency electrode and exposing at least the distal portion of the frequency electrode, handle means coupled to the proximal extremity of the elongate probe member, the handle means including hand operable means secured to the radio frequency electrodes for advancing and retracting the radio frequency electrodes with respect to the elongate guide means. 
     
     
       23. The device as in claim 22 wherein the distal extremity of the elongate guide means has a curvature for directing the radio frequency electrodes sidewise of the longitudinal axis. 
     
     
       24. The device as in claim 22 wherein the handle means includes means for bending the distal extremity of the elongate guide means to control the direction of penetration of the radio frequency electrodes in the tissue. 
     
     
       25. A medical device for the treatment by radio frequency ablation of a target volume in tissue of a prostate of a human having a urethral channel extending into a base of a bladder along a longitudinal axis comprising an elongate probe member having proximal and distal extremities and having a passage therein extending from the proximal extremity to the distal extremity, the elongate probe member being sized so that it can be introduced into the urethra, guide means mounted in the passage of the elongate probe member and having proximal and distal extremities, the guide means having a lumen extending therethrough from the proximal extremity to the distal extremity, a radio frequency conductive electrode disposed in the lumen and having a distal portion, an insulating sleeve disposed about the radio frequency electrode and exposing at least the distal portion of the radio frequency electrode, handle means coupled to the proximal extremity of the elongate probe member, the handle means including finger actuatable means secured to the radio frequency electrode for advancing and retracting the radio frequency electrode with respect to the guide means, the distal extremity of the guide means having a curved surface for directing the radio frequency electrode sidewise of the longitudinal axis into the tissue of the prostate. 
     
     
       26. A device as in claim 25 wherein the handle means includes means secured to the proximal extremity of the guide means for causing bending of the distal extremity of the guide means to thereby control the direction of penetration of the radio frequency electrode into the tissue. 
     
     
       27. A device as in claim 25 wherein the radio frequency electrode is movable longitudinally relative to the insulating sleeve. 
     
     
       28. A medical device for the treatment by radio frequency ablation of a target volume in tissue of a prostate of a human male having a bladder with a base and a penis with a urethra therein formed by a urethral wall extending into the base of the bladder along a longitudinal axis with the tissue of the prostate surrounding the urethra near the base of the bladder comprising an elongate probe member having proximal and distal extremities and having a passage therein extending from the proximal extremity to the distal extremity, the elongate probe member being sized so that it can be introduced into the urethra, a plurality of guide tubes mounted in the passage of the elongate probe member and having proximal and distal extremities with portions between the proximal and distal extremities, means for fastening together said portions of the plurality of guide tubes, each of the guide tubes having a lumen extending therethrough from the proximal extremity to the distal extremity, a radio frequency conductive electrode disposed in each lumen and having respective distal portions, an insulating sleeve disposed about each of the radio frequency electrodes and exposing at least the distal portion of the radio frequency electrode, handle means coupled to the proximal extremity of the elongate probe member and including hand operable means secured to the radio frequency electrode in each lumen whereby the radio frequency electrode in each lumen can be advanced and retracted with respect to the guide tube. 
     
     
       29. The device as in claim 28 wherein the handle means includes means for bending the distal extremity of each of the guide tubes to control the direction of penetration of the radio frequency conductive electrodes in the tissue. 
     
     
       30. The device as in claim 28 wherein the distal extremity of each of the guide tubes has a curvature for directing the radio frequency conductive electrodes sidewise of the longitudinal axis. 
     
     
       31. A medical device for use with an elongate probe member to treat by radio frequency ablation a target volume in tissue of a prostate of a human having a urethral channel extending into the base of a bladder along a longitudinal axis, the elongate probe member having proximal and distal extremities and being sized so that it can be introduced into the urethra and having a passage extending from the proximal extremity to the distal extremity, comprising a guide member adapted to mount in the passage of the elongate probe member and having proximal and distal extremities, the distal extremity of the guide member being in the vicinity of the distal extremity of the elongate probe member when the guide member is mounted in the passage of the elongate probe member, the guide member having a lumen extending therethrough from the proximal extremity to the distal extremity, a radio frequency conductive electrode disposed in the lumen of the guide member and having a distal portion, an insulating sleeve disposed about the radio frequency electrode and exposing at least the distal portion of the radio frequency electrode, handle means coupled to the proximal extremity of the guide member and including hand operable means secured to the radio frequency electrode for advancing and retracting the radio frequency electrode with respect to the guide member, the distal extremity of the guide member having a curved surface to direct the radio frequency electrode sidewise of the longitudinal axis into the tissue of the prostate. 
     
     
       32. A device as in claim 31 wherein the radio frequency electrode is movable longitudinally with respect to the insulating sleeve.